<template>
  <div class="pdf" style="width: 100%;">
    <div class="show">
      <pdf
        ref="pdf"
        :src="pdfUrl"
        :page="pageNum"
        :rotate="pageRotate"
        @password="password"
        @progress="loadedRatio = $event"
        @page-loaded="pageLoaded($event)"
        @num-pages="pageTotalNum = $event"
        @error="pdfError($event)"
        @link-clicked="page = $event"
        style="width: 800px; height: 500px"
      >
      </pdf>
    </div>
    <div class="pdf_footer">
      <div class="info">
        <div>当前页数/总页数：{{ pageNum }}/{{ pageTotalNum }}</div>
        <div>进度：{{ loadedRatio }}</div>
        <div>页面加载成功: {{ curPageNum }}</div>
      </div>
      <div class="operate">
        <div class="btn" @click.stop="clock">顺时针</div>
        <div class="btn" @click.stop="counterClock">逆时针</div>
<!--        <div class="btn" @click.stop="prePage">上一页</div>-->
<!--        <div class="btn" @click.stop="nextPage">下一页</div>-->
        <div class="btn" @click="scaleD">放大</div>
        <div class="btn" @click="scaleX">缩小</div>
<!--        <div class="btn" @click="pdfPrint()">打印所有指定页</div>-->
<!--        <div class="btn" @click="pdfPrintAll()">打印所有</div>-->
<!--        <div class="btn" @click="logContent()">获取页面信息</div>-->
        <div class="btn" @click="fileDownload(pdfUrl, 'pdf文件')">下载</div>
      </div>
    </div>
  </div>
</template>

<script>
import pdf from "vue-pdf";
export default {
  name: 'MyPdf',
  props: {
    // 当前pdf路径
    pdfUrl: {
      type: String,
      default:
        "https://yangfan-shop.oss-cn-hangzhou.aliyuncs.com/pdf/demo.pdf",
    },
  },
  components: {
    pdf,
  },
  data() {
    return {
      // 总页数
      pageTotalNum: 1,
      // 当前页数
      pageNum: 1,
      // 加载进度
      loadedRatio: 0,
      // 页面加载完成
      curPageNum: 0,
      // 放大系数 默认百分百
      scale: 100,
      // 旋转角度 ‘90’的倍数才有效
      pageRotate: 0,
      // 单击内部链接时触发 (目前我没有遇到使用场景)
      page: 0,
    };
  },
  watch: {},
  computed: {},
  created() {},
  mounted() {},
  methods: {
    //下载PDF
    fileDownload(data, fileName) {
      let blob = new Blob([data], {
        //type类型后端返回来的数据中会有，根据自己实际进行修改
        type: "application/pdf;charset-UTF-8",
      });
      let filename = fileName || "pdf.pdf";
      if (typeof window.navigator.msSaveBlob !== "undefined") {
        window.navigator.msSaveBlob(blob, filename);
      } else {
        var blobURL = window.URL.createObjectURL(blob);
        // 创建隐藏<a>标签进行下载
        var tempLink = document.createElement("a");
        tempLink.style.display = "none";
        tempLink.href = blobURL;
        tempLink.setAttribute("download", filename);
        if (typeof tempLink.download === "undefined") {
          tempLink.setAttribute("target", "_blank");
        }
        document.body.appendChild(tempLink);
        tempLink.click();
        document.body.removeChild(tempLink);
        window.URL.revokeObjectURL(blobURL);
      }
    },

    //放大
    scaleD() {
      this.scale += 5;
      this.$refs.pdf.$el.style.width = parseInt(this.scale) + "%";
    },

    //缩小
    scaleX() {
      // scale 是百分百展示 不建议缩放
      if (this.scale == 100) {
        return;
      }
      this.scale += -5;
      console.log(parseInt(this.scale) + "%");
      this.$refs.pdf.$el.style.width = parseInt(this.scale) + "%";
    },
    // 切换上一页
    prePage() {
      var p = this.pageNum;
      p = p > 1 ? p - 1 : this.pageTotalNum;
      this.pageNum = p;
    },
    // 切换下一页
    nextPage() {
      var p = this.pageNum;
      p = p < this.pageTotalNum ? p + 1 : 1;
      this.pageNum = p;
    },
    // 顺时针选中角度
    clock() {
      this.pageRotate += 90;
    },
    // 逆时针旋转角度
    counterClock() {
      this.pageRotate -= 90;
    },
    // pdf 有密码 则需要输入秘密
    password(updatePassword, reason) {
      updatePassword(prompt('password is "test"'));
      console.log("...reason...");
      console.log(reason);
      console.log("...reason...");
    },
    // 页面加载成功  当前页数
    pageLoaded(e) {
      this.$emit("current", e);
      this.curPageNum = e;
    },
    // 异常监听
    pdfError(error) {
      console.error(error);
    },
    // 打印所有
    pdfPrintAll() {
      this.$refs.pdf.print();
    },
    // 打印 第一页和第二页
    pdfPrint() {
      // 第一个参数 文档打印的分辨率
      // 第二个参数 文档打印的页数
      this.$refs.pdf.print(100, [1, 2]);
    },
    // 获取当前页面pdf的文字信息内容
    logContent() {
      this.$refs.pdf.pdf.forEachPage(function (page) {
        return page.getTextContent().then(function (content) {
          let text = content.items.map((item) => item.str);
          let allStr = content.items.reduce(
            (initVal, item) => (initVal += item.str),
            ""
          );
          console.log(allStr); // 内容字符串
          console.log(text); // 内容数组
        });
      });
    },
  },
}
</script>

<style scoped>
.pdf{
  padding: 20px;
}
.pdf>.show {
  overflow: auto;
  margin: auto;
  width: 900px;
  height: 550px;
}
.pdf>.pdf_footer {
  position: sticky;
  width: 750px;
  margin: 0px auto;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 10px 0;
  background-color: rgba(255, 255, 255, 0.5);
}

.pdf>.pdf_footer>.operate {
  margin: 10px 0 0;
  display: flex;
  flex-wrap: wrap;
}
.pdf>.pdf_footer>div {
// width: 80px;
  text-align: center;
  font-size: 15px;
}
.pdf .pdf_footer>div>.btn {
  cursor: pointer;
  margin: 5px 10px;
  width: 120px;
  border-radius: 10px;
  padding: 5px;
  color: #fff;
  background-color: #3dcbbc;
}


.pdf>.pdf_footer>.info {
  display: flex;
  flex-wrap: wrap;
}
.pdf>.pdf_footer>.info>div {
  width: 30%;
}
</style>
